The supply of electrical energy to a machine often needs to be interrupted to allow for maintenance on the components of the machine. The person conducting the maintenance may need to access parts of the machine that could be harmful if energy is being supplied to the machine. The machine may have exposed electrical terminals, or the electrical energy may cause movement to the components that could cause physical harm to the person. The machine may be of such a size that the person is maintaining a part of the machine that is remote from the electrical switch, and the switch may be inadvertently turned on causing harm to the person maintaining the machine. Alternatively multiple people may be conducting separate maintenance tasks on the machine, and it may not be clear that all those tasks are complete. One person may have left to collect replacement parts only to have the switch turned on in their absence. This may cause damage to the person when they return, or even damage the machine. It is therefore desirable to lockout the machine from the electricity source.
The switch controlling the supply of electrical energy to the machine is often located within a box, whereby the lid to the box can be locked in a closed position with a padlock. The box may include a metal hoop, often referred to as a staple, which fits through an opening in the lid and receives the shackle of the padlock. Alternatively the switch may include an aperture, which is exposed when the switch is in an “off” position, that accommodates the shackle to prevent it being moved to the “on” position. It is generally desirable for each person maintaining the machine to have their own padlock, however the size of the aperture or staple will generally only accommodate a single shackle. Where more than one person is maintaining the machine, it is preferred to provide a safety lockout hasp as it can accommodate more than one padlock.
A safety lockout hasp generally includes a shackle that can be attached to the aperture or staple. The shackle of the hasp can be moved to an open condition for attaching the hasp to the staple, and then moved to a closed position. The shackle of the hasp is retained in its closed position when a padlock is secured to the hasp. The hasp includes a plurality of apertures, each aperture for accommodating the shackle of a padlock. The plurality of apertures allows each person maintaining the machine to attach their padlock to the hasp, so that the shackle of the hasp can not be moved to the open condition without each of the padlocks being removed.
One problem with the shackle of the hasp is that it requires the plant to include features, such as a staple, that is specifically designed to accommodate it. It will be appreciated that not all plant will include the necessary features to accommodate the shackle. It may be the case that the plant was not designed with these features, or that the features have been subsequently obscured, damaged or destroyed. The plant may include other features not specifically designed for use with a shackle of the hasp, but still could be utilised to prevent operation of the plant. Unfortunately the shackle is not particularly adaptable for accommodating those other features.
Another problem with existing hasps is that the padlock can be attached to the hasp without the shackle of the hasp being in the closed condition. This can result in the hasp being attached to the machine, a padlock being attached to the hasp, and yet the hasp is still not in a closed condition. This will allow for the hasp to be detached from the machine while a padlock is attached, and more critically allow for electricity to be supplied to the machine.
A reference herein to a patent document or other matter which is given as prior art is not to be taken as an admission that that document or matter was, in Australia, known or that the information it contains was part of the common general knowledge as at the priority date of any of the claims.
According to this invention there is provided a safety lockout hasp for interaction with plant, the hasp including, a body, a cable for engaging the plant, a movable member being movable relative to the body between an open condition and a closed condition, the movable member interacts with the cable such that in the closed condition an intermediate portion of the cable is secured in its position relative to the body, the movable member also interacts with the body such that in use in the closed condition the hasp can accommodate a plurality of locking means so that in use the hasp is prevented from disengagement from the plant when accommodating at least one of the plurality of locking means, and when the movable member is in the open condition the hasp is prevented from accommodating any of the locking means.
The movable member may take any form however it is preferred that it includes a clamp portion that when the movable member is in the closed condition engages the intermediate portion of the cable. The degree to which the clamp portion engages the cable may vary however it is preferred that the engagement hinder the ability of the cable to be pulled from the body of the hasp. The body preferably includes an abutment portion which combines with the clamp portion of the movable member to engage the cable when the movable member is in the closed position, however the clamp portion may be formed with its own abutment portion. It is preferred that the clamp portion and/or the abutment portion includes at least one tooth which resiliently deforms the intermediate portion of the cable when the movable member is in the closed condition. This preferably enhances the ability of the hasp to hinder the ability of the cable to be pulled from the body of the hasp.
The movable member can move relative to the body in any suitable way, however it is preferred that the movable member pivots relative to the body when adjusting between the open and closed conditions. Alternatively the movable member may translate rather than pivot, for example. It is preferred that the hasp include biasing means for biasing the movable member towards the closed condition. The biasing means may take any suitable form including but not limited to a torsion spring.
The movable member preferably includes an engaging portion for additionally or alternatively engaging the plant, whereby when the movable member is in the open condition the engaging portion can engage and disengage from the plant, and when in a closed condition the engaging portion is prevented from engaging and disengaging from the plant when the hasp is accommodating said at least one locking means. The engaging portion may take any form however its preferred form is a shackle.
It is preferred that the movable member includes a lock receiving portion which accommodates the plurality of locking means. This may take any form however in the preferred form the lock receiving portion includes a plurality of apertures each extending through the lock receiving portion with each aperture configured to accommodate one of said plurality of locking means. It is preferred that the apertures in the lock receiving portion are obscured when the movable member is in the open condition so as to prevent accommodating any of the locking means. Obscuring the apertures prevents the operator from attaching a lock to the hasp to thereby reduce the likelihood of the plant being operational while the operators lock is attached. It is preferred that the locking means is a padlock and each aperture in the lock receiving portion is configured to accommodate a shackle portion of the padlock, however this may vary. When a padlock is used by the operator it is preferred that the shackle of the padlock abuts the body when preventing movement of the movable member from the closed position.
It is preferred that the movable member be fixed to the body and the body includes a pair of stops that limit movement of the movable member between the open and closed conditions. This reduces the likelihood that the movable member will be separated from the body rendering the hasp inoperable. It is further preferred that the body includes a cable aperture to receive the cable adjacent a proximal end thereof, the cable having an enlarged proximal end to prevent the cable from being pulled through the cable aperture so as to relatively fix the cable to the body. It is preferred that the cable includes a block at a proximal end which abuts the body surrounding the cable aperture to prevent the cabled being pulled through. Again this reduces the likelihood that the cable will be separated from the body rendering the hasp inoperable.
It is preferred that the body includes a further aperture which in use can accommodate a further lock means or further hasp so as to prevent movement of the movable member from the closed position. The location of the further aperture may be in any suitable location however it is preferred that the body is formed with a front wall and a rear wall, wherein the further aperture extends through the front wall and the rear wall. It is further preferred that the movable member and body are arranged such that the movement of movable member from the closed condition obscures the further aperture.
It will be convenient to hereinafter describe the invention in greater detail by reference to the accompanying drawing showing a preferred embodiment of the invention. The particularity of the drawings and the related detailed description is not to be understood as superseding the generality of the proceeding broad description of the invention.